Enterprise systems may comprise multiple instances of application software. Such applications may be individually licensed to users within the enterprise on demand. In order to enforce licensing schemes, the allocation of licenses in response to requests to access licensed resources can be controlled by license servers. Specifically, a license server can allocate a required license in response to a valid request, so long as such license certificates remain available. If a requested license is not available, the license server can deny access to the associated resource.
In order to prevent the cloning of license servers and their associated license certificates, requests for such certificates can be required to be associated with a valid media access control (MAC) address or other tie to physical hardware. However, because such an approach is hardware centric, it is ineffective when the license server is in a virtual environment. In order to support the allocation of licenses in a virtual environment, a persistent connection between an external license authority and the licensed system can be maintained. In such a system, real time or near real time information regarding the number and types of license certificates that have been allocated for use within a system is provided to the license authority. However, such systems cannot be used if a persistent connection to the licensed system is unavailable. For example, secrecy or privacy concerns may result in a refusal by the system operator to allow access to their network by an external authority. As a result, it can be difficult or even impossible for licensors to verify that software licenses are not being replicated, either accidentally or intentionally, by the system operator.
As alternatives to maintaining a persistent external connection in order to enforce licensing schemes, license rights can be tied to particular hardware characteristics, such as a processor identifier in addition or as an alternative to a network interface MAC address. Such approaches can allow customers to move between different license servers, but they require that the customer return to the license authority to perform a license re-host transaction to update the license file to reflect the MAC address of the new server. However, such approaches are inapplicable to virtualized environments. Other schemes require shipping unique physical software copies, such as individual CDs, that have embedded identifiers and inflexible licensing mechanisms to end users. However, such schemes are also ineffective in virtualized environments.